How cheap is the 975? If it was for a good price definitely go for the 975 and pick your self up a nice cooler.
well we are probably talking about between $10-20, What is the difference? I have read a lot about that the 920/w3520 gives nearly the same result when overclocking to high values?
I would say go for it, the 975 is still a very capable chip and for 20 dollars thats a steal.
From what i can see the 975 is clocked a bit higher than the Xeon.